Apparatus fob testing bevel-gear teeth



March 20, 1928.

C. H. LOGUE APPARATUS FOR TESTING BEVEL GEAR TEETH 4 Sheets-Sheet 1 Filed April 16. 1926 I NV NroR March 20, 1928. 1,663,085

c. H. LOGUE APPARATUS FOR TESTING BEVEL GEAR TEETH Filed April 16. 1926 4 Sheets-Sheet 2 March 20, 192s. 1,663,085

C. H. LOGUE APPARATUS FOR TESTING BEVEL GEAR TEETH Filed April 16. 1926 4 Sheets-Sheet 5 )hv-Nass y )W ByMTToz/VEYS C. H. LOGUE APPARATUS FOR TESTING BEVEL GEAR TEETH March 20, 19,28.

4 Sheets-Sheet 4 Filed April 16, 1926 6%; l/NTR x77 RNEYS Patented Mar. 20, i928.

ni stares .ears

Leases CHARLES H. LOGUE, OE SYRACUSE, NEW YORK, .ASSIG'NOR TO THE GEAR GRINDLNG BIAGI-HNE CDIVIPANY, F DETROIT, MICHIGAN.

APPARATUS FOR TESTING BEVEL-GEAR TEETH.

Application filed April 16, 1926. Serial No. 102,368.

This invention relates to a method of and apparatus tor testingthe teeth et bevel gears Jtor the purpose ot locating any inaccuracy or error which may exist in the profile or contour of any tooth Vso that the imperfection may be expeditiously remedied by regrinding or other suitable treatment.

In bevel gears the cone angles, apexdis- 'tances and angles ot Obliquity of the teeth and ,also the cutting radius of spiral teeth are usually known or may be easily calculated to :term abasis reasonably accurate tor the construction. ot the mechanism einployed in testing the cont-our or profile ot the teeth which, as previously stated consists in rolling the gear under test about the apex ot' its cone with the tace oit one ot its teeth in Contact with the tace of a test tooth of similar angular Obliquity and simultaneously measuring the relative motion of one ot the parts due to inaccuracy in the forma-l tion of the tooth under test.

The main obj ect is to provide amore practicable, expeditious and efficient method for determining the presence ot imperfections in the teeth of bevel gears than has heretofore been practised by simply rolling the gear about the apex of its cone with the tooth under test in contact with a master tooth ot the same angular obliquity.

One ot the speciiic objects is to support the gear upon a co-axial rolling carriage having a. conical surface corresponding to the pitch cone and apex distance ot' the gear and adapted to roll along and upon a substantially flattrach or supporting surface which is co-incident with one side of the pitch cone of the gear so that the rolling motion of the carriage along its track will impart a corresponding rolling motion of the gear under `test in a manner similar to the action Yof companion gears when their teeth are theoretically perfect so that when the gear under test is rolled along the track with its tooth under test rin contact with a. master tooth any appreciable imperfection in the prolile or contour ot the tooth will produce a corresponding movement of the master tooth which movement may be registered by the application of a suitable dial tester thereto.

Other objects and uses relating to specific parts of the device will be brought out in the following description.

In the drawings Figure l is a top plan of one :form of my invention for testing the teeth of spiral gears and also showing by dotted lines the manner of testing radial teeth of beveled gears.

Figure 2 is a vertical sectional view taken on line 2 2, Figure 1, showingl the means tor testing straight teeth.

Figure 3 is a side elevation ot the carrier .for the master tooth together with av dial indicato-r on the carrier shown in Figure l for indicating movements ot' the master tooth due tol inaccuracies in the gear tooth under test when in rolling contact therewith.

F igurev et is a top plan similar to Figure l except that the apex ot' the cone lor the gear under test is in `offset relation to that of the gear with which it is adapted to mesh.

Figure 5 isa top plan similar to Figure tshowing a modified supporting means for themaster or testy tooth.

Figure 6 is a top plan of a further modified. form ot' my invention in which the pinion under test is rolled about its apex in clontactfwith the teeth ot a master gear having means tor operating an indieatorin ease the master gear should be moved about its axis by imperfections in the teeth ot the pinion.

, Figure is ay sectional View taken on line 4 4, Figure 6.

Figure 8 is a top plan of a further modiication for testing the teeth of gear-rings in which the gear support is adapted to roll about its apex with its teeth in contact with movabletest tooth, the gear ringbeing shown by dotted lines.

Figure 9 is an enlarged sectional view taken on line 9 9,l Figure 8, showing the gear ring in testing position.

Figure l0 is a top plan, partly in section, of the supporting bed and indicator shown in Figures 8 and 9.

The device shown in Figure l is adapted to be usedfor testing the teeth of spiral gears and comprises a main supporting bed 1 having one or more circular traclr surfaces -2- which are preferably disposed in a horizontal plane of and concentric with the apex as -aof the pitch cone as -a of the gear as -A- under test.

This gear is mounted upon a carriage -3- having annular' conical rims -4. coincident with the cone pitch lines -aof the gear -A- under test adapted to roll along and upon the track surfaces 2- about the apex zof the gear cone.

The carriage -3- comprises a hollow member -5 and a mandrel -6- axially extending therethrough and co-axial therewith.

The gear -A- is preferably provided with a tapered bore and fitted tightly upon a tapered portion -6- of the mandrel 6m which is provided with threaded ends engaged by nuts -7- and -7- by which the gear -A- is clamped to the mandrel and the mandrel firmly clamped to the member -5- so that the gear may roll with the carriage about the apex -aof the geai` cone, it being understood that the gear *A* will be supported the proper radial distance from said apex corresponding to the radius of the companion gear with which it is adapted to mesh and that the carriage 3 is preferably rolled along the, track surl 'faces E2-'- by hand in testing the teeth of the gear -a-r The means foi-detecting the errors or imperfections in the contour or profile of the teeth of the gear -A-comprises a master tooth 8- mounted yieldingly through the medium of one or more spring arms -9 upon one end of a supporting arm -10- having its other end pivoted by trunnions -llm to a suitable bracket, -12- which in turn is supported by relatively movable slides 13- and -llupon the main supporting frame or bed -l-.

The slide -l3- is movable along a rec tilinear guideway -l9- in the meinbe `1i which in turn is movable in a rectilinear guideway lil in the main sup porting frame or bed nl substantially tangential to the companion gear B- shown by dotted lines in Figure l, said guideways being disposed at right angles to each other to permit the axis of the swinging arm l0- to be adjustcd'to a position approximately co-incident with the center of curvature of the spiral teeth of the gear da* when the latter is rolled to its testing position in contact with the test tooth -8-.

That is, the distance, between the axis of lmovement' of the swinging arm -l0-- and axis of the test tooth -8- corresponds approxin'ia-tely to the radius of curvature of the spiral teeth of the gear under test and the sliding members M18- and i4- permit the axis of the swinging arm -lOw to vvbe adjusted to approximately the center of said curvature parallel with the axis of the companion gear B Y The supporting arm -10- for the test tooth -8- is arranged to support said test tooth directly under and in contact with the tooth at thelower side of the gear -A-- when the axis of said gear is brought to a position directly over the point of the test tooth or other testing position.

This test tooth -8- is tapered at an angle to correspond to the angle of Obliquity of the gear teeth under test and is adapted to enter the space between adjacent teeth leaving suflicient clearance for movement of the test tooth against the action of its retracting springs -9- by any inaccuracy which may exist in the profile of the Surface of the tooth under test.

Suitable scales and 16m may be provided upon the sliding member 4l/iand main supporting bed leto facilitate the proper position of the axis of the arm m10- at the cent-er of curvature of the gear'v tooth under test and also to properly position the test tooth -8- at the testing point.

Any suitable means may be employed for measuring or indicating movements of the test tooth -8- by imperfections in the contour of the tooth under test during the testing operation, said means consisting in this instance of the standard form of dial indiator --C- mounted upon the arm -l(l` and provided with the usual plunger c adapted to contact with one side of the spring support for the test tooth as shown more clearly in Figure In testing the teeth of spiral gears the slides -13- and letare first adj ust ed to bringr the axis of the radius arm -10- at approximately the center ot curvature of the tooth of the gear when the latter is brought to the'testing position, the radius arm 10- being then adjusted about its axis to bring the test tooth *8- into contact with the gear tooth under test.

Then by rolling the carriage --3* bacl; and forth along the track surfaces -2- di'l ferent portions of the face of the tooth under test will be brought into contact with the test tooth n8- in a manner similar to the action of the teeth of the -gear under test with the teeth of its companion gear.

If, during this rolling action of the carriage -l along the track surfaces --Q--` any imperfection in the prolile or contour of the. tooth surface under test exists it willl move the test tooth laterally against the action of its springs -9- and plunger -cthereby effecting the operation of the pointer of the indicator to show the position and amount of error in said profile or contour.

titl! The `carriage -3- with the gear to he tested thereon is'easily portable and is free it to be adjusted angula-rly for repeating the testing operation upon all of the teeth, it being understood that the indicator -C- and its plunger -cwill be arranged at the side of the test tooth 8* opposite that Which engages the tooth surface under test.

In testing bevel gears having straight or radial teeth a bracket as 12- as shown in Figure 2 is supported in a socket or opening -12- co-axial with the axis companion gear -B- or co-incident with the cone apex of the gear under test thus bringing the axis of movement of the radius arm as -lO- in the same co-axial relation to the companion gear and cone apex so that the test tooth -8 maybe brought into contact with the face of the tooth under test or When the axis of the gear -A-, test tooth 8* and swinging arm -10-- are in the same vertical plane.

Under these last-named conditions the carriagel -3* and` gear A- under test may be rolled along the track surfaces in the manner previously described for testing the accuracy of the teeth through the medium of the test tooth --S in which case an indicator as -C- may be placed upon a supporting ledge as -cof the base 1- ivith its plunger -c-in contact with a surface -9- on the vhead of the arm -flO- for indicating any lateral swinging movement of the test tooth -8- due to imperfections in the contour of the tooth under test.

The base -lis preferably provided with a pair of guides -14- at opposite sides of the cone apex -ato permit the use of the testing device for testing opposite faces of each gear tooth.

rIhe construction shown in Figure l is substantially the same as that described for Figures l and 3, except that the axis of the cone of the gear is oifset to one side of the axis of the companion gear and that the angle of inclination of the teeth under test is somewhat less than that shown in Figure l necessitating the adjusting of the testing device along the guides ].3-- and 14- to different positions than is shown in Figu'pe l3 otherwise the same reference letters apply to the construction shown in Figure 4.

The construction shown in Figure is also quite similar to that shown in Figure 4 except that the supporting slide for the radius arm v--1O- is mounted directly upon a fixed guide -14 on the bed -ldiametrically of the companion gear -B- and that the slide as -13- is adjusted so as to bring the axis of movement of the arm co-axial with the companion gear -B- with the test tooth in contact with the gear tooth under test in which. case a dial indicator similarl to that shown in Figures 9 and 10 may be placed upon the upper surface of the supporting bed With its plunger in contact with one side of the free end of the arm -lO- for indicating any lateral movement of said arm due to inaccuracy in the contour of the tooth under test.

ln Figures 6 and 7 is shown a device for testing` gear rings in Which a master gear ring -l8 is mounted upon a revoluble carrier -19 having a co-axial stem 20- journaled in suitable bearings El*- and 22h on a main supporting bed or frame 23-- The gear as -L- under test is mounted upon a rolling carriage 24- having coaxial annular bearings -25- movable along circular track surfaces 2- simila-r to the track surfaces -2- except that they-are disposed in an inclined .plane passing through the conical apexes of the gears Ak and -18`-.

The track surfaces -26 are concentric With the axis of the master gear 1S- and also with the conical apex -aaround which the carriage -24- is adapted to be rolled and for this purpose is provided with a hand Wheel -27- movable 1n a circular guidevvay 28- in the bed -23-. Secured to the hub or stem of the angularly movable table -l9- is a test arm 30- extending through an opening 3lin one side of the bed -23- and having its free end adapted to contact with the plunger -cof an indicator -C- which is supported upon the outer surface of the bed 23-- A coiled spring -32- is secured at one end toa bracket -33- on the bed 2S- and has its other end connected to the free end of the arm for yieldingly holding the teeth of the master gear -18- in contact with the teeth of the gear -A- under test to avoid backlash or lost motion between the teeth of both gears and thereby to assure a more accurate testing of the teeth of the gear AL-7 it being understood that the spring -32- is rather light and just sufficient lto maintain the desired contact between the teeth of said gears.

In testing the gear -AH the carriage 42% with the gear thereon is rolled along the track surface -26- about the conical apex ctand in contact with the teeth of the master gear l8- and if any inaccuracies exist in the contour of the teeth of the gear At it will be transmitted to the master gear and thence through the table -19- and arm -30- to the indicator -C- to enable the operator to locate such inaccuracy for subsequent correction.

In Figures 8 to 10 inclusive a beveled gear ring -y to be tested is secured by bolts -Lilto a carrier -42- Which is adapted to be rolled around the apex as -aof the pitch cone of the gear i0` upon a track surface -43- of a. supporting bed *4%.

The rolling carriage 42- for the gear ring -40- is preferably composed of circular co-axial sections aand -46-- secured together by a co-axial bolt -47-, the section -46- being provided with an annular conical tace --48- adapted to roll along upon the track surface 4B- about the apex Mazsaid section #-46%- being provided with a central ball w49- seated in a spherical socket to form therewith a universal joint whereby the entire carriage may be not only rolled about the apex -abut may also be tilted to permit it to be adjusted angularly for registering different teeth with the master tooth as -Q-- This master tooth is mounted upon the iree end of a sumiorting,r arm -l0- which is `pivoted by trunnions -ll-- to the bed 4t-4 to swing in an opening -44-- therein, the axis ot movement of said arm being in line with'the cone apex -a-.

A dial indicator (1- is mounted upon the bed .-414- with its plunger en in contact with one side ot' the free end of the arm -IO- as shown in Figure tor transmitting motion v'from said arm to the pointer of the dial in case the arm should be moved laterally following imperfections in the prolile or contour of the gear tooth under test.

It will be noted. that in all ot the modifications shown and described the bevel gear under test is movable about the apex of its .pitch cone with the tace of one or more of its teeth in contact with a master tooth or gear from which motion is transmitted to an indicator as -C in case ot imperfections in the contour ot the gear tooth 'for not only locating the imperfections for indicating the amount ot deviation from a perfect contour.

lVhat I claim is:-

l. In a device tor testing the-teeth of bevel gears, a test tooth, movable supporting means for said tooth, means for supporting the gear to move about the apex of a cone corresponding to the pitch cone of the gear with a tooth ot the gear in contact with the test tooth.

2. In a device tor testing the teeth of bevelgears, a test tooth, movable supporting means for said tooth, means tor supporting the gear to move about the apex ot a cone corresponding to the pitch cone of the gear with a tooth of the gear in contactwith the test tooth, and means for measuring the amount oit' movement ot the test due to inaccuracy in the contour ot the gear tooth under test.

3. A device for testing bevel gear teeth comprising revoluble supporting means for thc gear under test movable about the apex of a cone corresponding` to the cone pitch ot the gear, means caused by said movement for etfecting a rotary motion of the gear about its axis, a movable test tooth, and means for movably supporting the test tooth in position to mesh with the gear teeth Vunder test whereby an error in the prolile of the tooth being tested will cause a movement of the test tooth.

4.-. A device for testing bevel gear teeth comprising revoluble supporting means Jfor the gear under test movable about the apex ol a cone corresponding to the cone pitch ot the gear, means caused by said movement for eii'ecting a 4rotary motion ot the gear about its axis, a movable test tooth,v and means for movably supporting the test tooth in position to mesh with the gear teethv under test whereby an error in the proiile of the tooth being tested will cause a movement of the test tooth, and means for indicating the amount of the last-named movement.

5. In a device for testing bevel gear teeth, a track surface, a conical roller in rolling contact with said surface about its apex, the angle of the cone of the roller corresponding to the cone angle oi the gear on the pitch circle, means for securing the gear under test co-axially to the roller to roll therewith, a master tooth, means for supporting the master tooth movably in contact with the gear tooth under test whereby an error in the profile of the gear tooth will etfect a Inovement of the master tooth und its supporting means, and means for indicating the amount of the last-named movement.

G. In a device for testing bevel gear teeth, means tor support-ing the gear under test to roll about the apex ot a cone corresponding to the cone pitch ofthe gear, a master tooth, and means for supporting the master tooth movably in contact with the gear tooth under test whereby an imperfection in the proiile of the gear tooth will effect a movementot' the master tooth and its supporting means.

7. In a device for testing bevel gear teeth, means for supporting the gear under test to roll about the apex oit a cone corresponding to the cone pitch of the gear, a master tooth, means for supporting themaster tooth movably in contact with the gear tooth under test whereby an imperfection in the pro- .tile oi the gear tooth will etllecta movement of the master tooth and its supporting means, and means for indicating the amount oiz movementof said master tooth and its supporting means.

8. In a device for testing bevel gear teeth, a circular track surface, a conical roller in rolling contact with said track surface about the axis ot the circular track, means for securing said gear co-axially to the roller with the apex of its conical angle in said axis, a master tooth supported movably in contact with the gear tooth under test to be moved by imi'ierfections in the gear tooth as the roller is rolled along the track surface, `and means for indicating the amount of vsaid movement of the Ymaster tooth.

9. In a device for testing bevel gear teeth,

lll)

a conical roller having means for supporting the gear to be tested With its pitch circle coincident with the conical angle of the roller, said roller being movable about the apex of its cone, a track surface along Which the conical roller is adapted to be rolled and a master tooth movably supported in one side of said angle and'in contact with the gear tooth under test whereby imperfections in said gear tooth Will cause movement of the master tooth during the rolling action of the gear.

10. In a device for testing bevel gear teeth, a conical roller having means tor supporting the gear to be tested with its pitch circle coincident With the conical angle of the roller, said roller being movable about the apex of its cone, a track surface along `Which the conical roller is adapted to be rolled and a master tooth movably supported in one side ot said angle and in contact With the gear tooth under test whereby imperfections in said gear tooth Will cause movement of the master tooth during the rolling action of the gear, and means for indicating the amount of movement of the master tooth.

11. In a device for testing bevel gear teeth,

a master tooth, means for rolling the bevel gear under test about the apex ot' a conical angle corresponding to the conical angle of the gear with one of its teeth in rolling contact with the master tooth, said master tooth being free to move due to imperfections in the gear tooth under test, means for supporting the master tooth, and means for indicating the amount of said movement of the master tooth.

12. A device for testing bevel gear teeth as in claim 11 in which the supporting means Jfor the master tooth includes a pivoted arm.

13. A device for testing bevel gear teeth as in claim 11 in which the supporting means for the master tooth includes a pivoted arm adjustable to different angles relatively to the axis of the gear under test.

14. A device for testing bevel gear teeth as in claim 11 in which the supporting means l'or the master tooth includes a slide adjustable transversely of the axis of the gear under test.

ln Witness whereof I have hereunto set my hand this 12th day of April, 1926.

CHARLES H. LOGUE. 

